Anyone using a PA amp in their home system?

you may benefit from the "few first watts in class A" from your pro amp if this one is a class AB amp ( Cause if its class H,G, T or D i dont think that it can be compaired in quality even with the most simple amplifier that is presented in the forum and that will be the DX amplifier from destroyer X )

then you have to live with tha blowers of your proamp

and then again you have to basically understand the diference of HIGH END amps and PRO amps ....

there is no diference ...!!! schematic wise are absolutely the same .... or based on the exact same idea the only things done diferent is : level of power /protection methods /quality of built /complexity

start removing most if not all potection methods from a pro amplifier that will be level limmiter VI limmiters bandwidth limmiters and you will end up with an almost high end amp with no protection at all risky ???? that is for you to answer

most pro amps are designed with first target of power then its quality then is safety then is cost then is watt/kg and so on

in high end amps is the totally oposite

and to my very simplified opinion ...
all class AB should sound absoloutelly the same if based more or less on the same circuit and the only thing that vary is the quality of built ....this is very simplified since a million of small details can make sound better or worst but the truth is that the diference lays beyond the above , to the balance beween safety and quality that a manufacturer will make ....

kind regards sakis
 
I'm using all pro amps for my 4way actives: MC2 Audio MC750, MC450, T500 and an Omniphonics Footprint (aka BeyerDynamic Blueprint).
The three MC2 amps are not just pro amps but also the best sounding amps I have come across regardless of cost or intended application.
According to MC2s designers Terry Clarke and Ian McCarthy they have been designed first and foremost for SQ and then made road-proof. I have found no reason to doubt them and the fans are surprisingly quiet. Used to have a QSC (JBL) amp at some time and I think 20 MC2 amps with fans running would be quieter than that one.
The reason I use the Omniphonics is that MC2s smallest amp produces 175w, a bit of overkill to drive a ribbon supertweet which takes 4w rms and I got it s/h for £20 incl. p+p.
 
my point exactly ... do you actually know what is the upper limmit for bandwidth for the amplifier that you use for your tweeters ??? i havent seen many of these comercial pro amps to have a usable bandwidth above 20khz .... now days in high end amplifiers bandwidth is blown to the moon ...at least ... seen things that working up to 200khz for fun ....( not that i usable in human hearing but if they still like to make it like this why not ???)
 

gil1

Member
2009-01-01 11:52 am
Reason for asking is that I just came across a Yamaha P2500 and dont know what class amp it is ( A, B, D, or H) but in any case it is a great sounding amp, the bass is fast and strong not boomy but the mids and highs are a bit loud, I was able to attenuate mids and highs with an equalizer and it is just a super sounding amp, Im very happy with it.

Now, I was wondering if manufacturers make these amps with a flat bandwidth or if they over emphasize a certain portion like the mids since they are geared more towards club/DJ use?
 
Reason for asking is that I just came across a Yamaha P2500 and dont know what class amp it is ( A, B, D, or H) but in any case it is a great sounding amp, the bass is fast and strong not boomy but the mids and highs are a bit loud, I was able to attenuate mids and highs with an equalizer and it is just a super sounding amp, Im very happy with it.

Now, I was wondering if manufacturers make these amps with a flat bandwidth or if they over emphasize a certain portion like the mids since they are geared more towards club/DJ use?

http://www.yamahaproaudio.com/downloads/documents/data/white_papers/yamahapoweramp_whitepaper_en.pdf
 
yeap ...i will agree with the above ...P2500 is made like that ... a classic AB amplifier switable for home listening "free" enough for hifi use , first few watts is in class A like all class Ab amps ( even though bias is quiet low and could be boosted a bit for home use and add to that a bit of temperature more ) and yes ...its made with quite good quality parts and yes ...again has protection methods that are not enough for this range of power resulting a reputation about these amps that are rowbust quality amps but will not forgive mistakes

good thing is that the protection methods will never kick in to the signal at hifi home use ( low power) but still exist in the signal path

i would say yes ... regarding this pro audio amp !!!

kind regards sakis
 
The beauty of MC2 MC series amps is that none of the protection circuitry is ever in the signal path. Even if the limiters kick in they merely roll off the supply rail voltage until things cool down a bit. Phoned their customer service once which connected me directly to Ian McCarthy. He assured me that in typical home use they are extremely unlikely to ever leave class a operation.
Down side is that they cost four times as much as the above mentioned Yamaha.
But then I bought mine s/h for £100 (T500) and £350 (MC450 and MC750) rather than £1000, £1500 and £1700 respectively.
I love ebay…

That said I like Yamaha amps, very good value for money and extremely good when comparing to equally powerful 'audiophile' amps!
 

wg_ski

Member
2007-10-10 5:21 pm
Reason for asking is that I just came across a Yamaha P2500 and dont know what class amp it is ( A, B, D, or H) but in any case it is a great sounding amp, the bass is fast and strong not boomy but the mids and highs are a bit loud, I was able to attenuate mids and highs with an equalizer and it is just a super sounding amp, Im very happy with it.

Now, I was wondering if manufacturers make these amps with a flat bandwidth or if they over emphasize a certain portion like the mids since they are geared more towards club/DJ use?

I believe the Yammies are a variant of class H, with a class AB lower tier and an upper tier that is class D. Response is flat as a pancake. If you're getting coloration, the amp may be showing flaws in your speakers.

Some of the cheaper pro amps roll off the extreme low bass below 20 (so they can use undersized reservoir caps) or the highs above 20k (for stability). Like the QSC RMX and GX, Behringer stuff, and the XTi1000. The next tier up tend to be flat at least 10-50k.
 

gil1

Member
2009-01-01 11:52 am
yeap ...i will agree with the above ...P2500 is made like that ... a classic AB amplifier switable for home listening "free" enough for hifi use , first few watts is in class A like all class Ab amps ( even though bias is quiet low and could be boosted a bit for home use and add to that a bit of temperature more ) and yes ...its made with quite good quality parts and yes ...again has protection methods that are not enough for this range of power resulting a reputation about these amps that are rowbust quality amps but will not forgive mistakes

good thing is that the protection methods will never kick in to the signal at hifi home use ( low power) but still exist in the signal path

i would say yes ... regarding this pro audio amp !!!

kind regards sakis

And how would you suggest to increase the bias and how much? I adjusted the idling current to specs and the DC is where it should be.

At the moment I think I will disconnect the fans since the unit runs very cool (actually cold to the touch) but I still like to know if there are any adjustments I can make for lower volumes, all my other home hi-fi amps get very warm at moderate to low volumes.
 
according to the service manual (which by the way is available email me if you want to have it ) its 15mv+-2mv across t TP 1 and TP2 check the rail voltage check the emmiter resistors value and do the math to see how much this is

amplifier like that could easily work with idles of 100 200 or even more milliampers but if it sound better after that its up to you to find out

make small changes taking one step at a time to see how it goes ... tune it for 15 mv then go to 25 for example to see if it makes audible diference .... If you do so double think before removing the vents ...things might get pretty warm

regards sakis
 
I've used a few smaller amps. An ab international 600a (some hiss and needed 4vrms for full output), altec 9440a (worked great), crown psa2 (again great), but other pa amps tend to sound grainy and glassy (crown dc300a and series 2). As a sub amp (dc300a) when I bridged the amp, the sub (18" in a keele w-bin) sounded much better than it did using 1 channel (600wrms vs 150 wrms), and not just at extreme levels, it was weird. My friend said that maybe I was clipping it and I had no idea.

The trouble with pa amp is they tend to run high feedback and the protection circuitry often harms the sound quality.

Norman
 
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I run three crown xti 2000,4000,6000 as a home/shed stereo.No problems except desire for four way instead of three.midd range amp from them but that was within my budjet.Have beeen doing a few sound reinforcement gigs.All good fun and interesting.I think HEADROOM is a very important aspect of it all,I run as high impeadence load as I can afford to keep distortion numbsre down a bit.I'm not a fan of Low frequency/low impeadence combination for saftey reasons.
 

kipman725

Member
Paid Member
2007-06-10 12:41 pm
Warrington
I started using a EP4000 for my sub this week. If a driver can take 400W RMS (PD.12SB30) very few home amplifiers can supply that, especially at low cost. Slightly overkill though the most I can bear before the rooms falling apart is 100Wish.

*not the subs in my sig they would die it's a new tapped horn

*no problems with hiss or background noise apart from fan, no problems with audio quality.

**I think the EP4000 is Class H with the upper rail at least +/-141V
 
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The AB Precedent Series 900A that I own has a very noisy fixed-speed fan; I've never used it at home. IIRC there are locations on a circuit board for temperature-controllinga fan, perhaps on a different model. I don't know for sure that this is the stock fan; when I got the amp, the fan had seized, so I replaced it with the same model. The air path is unusual: fan is on the side sucking in; air is blown out the back through a narrow slot and directed over the heatsinks. Cutting away the slot grille and using a wire grille should reduce the siren effect, and implementing variable speed would help. And maybe for home use the fan could be safely disabled altogether or replaced with something slow and quiet just to keep the inner temperature down.
 
I have a Qsc RMX2450 on subs and a Mackie 1400i on tops..in the entertainment center in my living room. the Qsc fan is loud, whereas the Mackie is so quiet, the only way to know it is running is to hold my hand on the side vent and feel for airflow. Sonically, I love the Mackie..and like I said, the QSC does it's work on the subs..